Pyrrolidine, also known as tetrahydropyrrole, is a saturated five-membered heterocyclic ring, which is miscible with water. Pyrrolidine exists in many alkaloids and drug molecules, such as kappa opioids, antagonists of dopamine D4 receptors, and HIV reverse transcriptase inhibitors.
Triazole refers to a heterocyclic compound with the molecular formula C2H3N3, which has a five-membered ring consisting of two carbon atoms and three nitrogen atoms. Neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease already affect many people around the world, and these numbers are increasing rapidly. Treatment for these disorders is often aimed at relieving symptoms and has no cure. Research on new molecules is underway, and heterocyclic compounds have important pharmacological implications. Triazoles and tetrazoles are emerging as new molecules in this field.
Incorporation of heterocycles into drug molecules can enhance physical properties and biological activity. Oxadiazoles are a class of five-membered heterocycles containing one oxygen and two nitrogen atoms with special biological activity and thermodynamic properties. 1,2,4- and 1,3,4-oxadiazoles are widely used in the development of bioactive molecules, but 1,2,5-oxadiazoles (furazans) are used relatively sparingly. Compared with 1,2,4- and 1,3,4-isomers, 1,2,5-oxadiazole has unique physicochemical properties and electronic effects. The furazan ring has a strong inductive effect, comparable to that of trifluoromethyl or tetrazolyl. The unique properties of furoxan can confer specific pharmacological activities to drug-like molecules.